As a food additive, nitrogen is a good gas. Both my country's GB 2760-2014 "National Food Safety Standard for Food Additives" and the FAO/WHO Joint Expert Committee on Food Additives (JECFA) clearly point out that nitrogen is a legal food additive. GB 2760 stipulates that nitrogen is a processing aid for the food industry, and the residual amount during the processing does not need to be limited. JECFA stipulates that nitrogen has the functions of refrigerant, packaging gas, etc., and it is clear that there is no need to stipulate the daily allowable intake (ADI value). Therefore, as long as nitrogen can reach the specified purity (nitrogen content is above 99.0%), it is very safe as a food additive. After all, 78% of the air we breathe is nitrogen.

There are two main functions of filling food with nitrogen

1. It can isolate the air, prevent some ingredients in food from oxidizing and deteriorating, and inhibit the growth and reproduction of microorganisms, such as potato chips and biscuits;

2. It can enhance the strength of the packaging, so that the product is not easily squeezed and deformed during transportation, such as beer, beverages, milk powder, etc.

Application of liquid nitrogen in the food industry

Nitrogen is a legal food additive, and nitrogen has been used in food quick freezing for many years at home and abroad. For example, the rapid freezing of seafood, poultry and other foods, because this method has a short freezing time, can make the ice crystals in the food smaller and more uniform, so that the taste and nutrition can be maintained to the maximum extent.
 

1. Application of liquid nitrogen in food quick freezing: fast freezing speed, good quality of fresh food, low material dry consumption, low equipment and power costs;

2. Application of liquid nitrogen in food processing: At present, many soft material manufacturers have replaced traditional CO2 with nitrogen or a mixture of nitrogen and C02 to inflate and package soft materials. Highly carbonated beverages filled with nitrogen cause fewer problems than soft materials filled with only carbon dioxide; nitrogen is also ideal for filling non-foaming beverages such as wine and juice. The advantage of adding liquid nitrogen to non-aerated soft material cans is that the small amount of liquid nitrogen injected can remove the oxygen in the top space of each can, making the gas in the upper space of the storage tank inert, thereby extending the storage period of perishables.

Beware of "Internet celebrity foods" with added liquid nitrogen

Some novel snacks and drinks add liquid nitrogen before consumption to create a "dragon mist" effect. When they are eaten, liquid nitrogen will spray out of the pores of the snacks, creating a visual effect of smoke emanating from the mouth. This kind of fairy food is mainly because liquid nitrogen is applied or added during processing. Liquid nitrogen is liquefied nitrogen. The temperature of liquid nitrogen is as low as -196℃. If food ingredients such as ice cream "go around" in liquid nitrogen, they are basically frozen and condensed instantly. At room temperature, liquid nitrogen will quickly vaporize and emit white smoke similar to fairy air.
 

Internet celebrity foods with added liquid nitrogen require us to be extra careful. If handled improperly or consumed insufficiently, it will cause serious damage to the skin and internal organs. Inhaling the vapor released by liquid nitrogen in food or drinks can also cause respiratory problems, especially for asthmatics. Because the temperature of nitrogen drops rapidly during the vaporization process, it freezes the water in the cells and constricts the blood vessels. These changes can cause skin cell death, skin frostbite, and sometimes even permanent damage. Extreme cold can also have similar effects on internal tissues. For those who eat liquid nitrogen smoke balls, liquid nitrogen may cause burns to the mouth, esophagus and upper respiratory tract, causing organ perforation or rupture. Inhalation of vapor by people with asthma or lung disease may cause airway constriction, triggering asthma attacks or worsening lung disease.
 

So don't hurt your body in pursuit of novelty. If you must try it, be sure to take effective anti-freeze measures, or choose a merchant with special cold-insulated containers. Liquid nitrogen must be completely evaporated from the food before the food is ingested. If frostbite occurs, be sure to seek medical attention immediately.